Maryland Cosmetology State Practice Exam

Physical properties are characteristics of a substance that can be observed or measured without altering the chemical composition of the substance. Option C relates to characteristics that determine the appearance or state of a substance, such as its size, color, weight, and hardness. These properties do not involve chemical reactions and can be observed or measured directly. Option A and D are incorrect because boiling point, melting point, electrical conductivity, and magnetism are all examples of physical properties, but they are already specified in option C. Option B is incorrect because reactivity and flammability are chemical properties, which involve changes to the substance's chemical composition.